2011-11-10_PERMIT FILE - C1984065A

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• slough was first noted during afield inspection conducted April 28, 1995. The stability study presented in Exhibit 4.7-5 indicates that inadequate vegetation and poor surface drainage can impact the stability of the slopes. That was exactly the condition that existed during the very wet spring of 1995. There was virtually no vegetation on site and surface drainage was inadequate in the area that sloughed. Even though one of the terraces sloughed, the outslopes of the terraces are considered to be stable because only one small portion of the bench outslopes failed during the period when all of the benches were the most susceptible to failure. The Operator proposes to reduce the slope in the area of the slough to repair the slough and to assure the area is stable in the future. The slope will be reduced by breaking the slope down with a track dozer. The slope in this local area will be reduced to a 3h:ly or less. The approximately 15 foot wide dozer slot will also provide a drainage path for run-off from the middle to lower bench. One or two additional dozer slots may be constructed in areas where water has accumulated on the middle bench. The proposed dozer slot is outlined on Figure 4.7-4. The Division requested the cut slope above the proposed coal stockpile area be partially backfilled. This area has also been referred to as the cut slope on the east end of the mine. The Operator proposes to reclaim the slope as presented on Figures 4.7-4 and 4.7-5, Section C-C'. Fill will be placed so the lower one third of the slope is reduced to a 3h:ly slope. The fill material will be obtained from the topsoil stockpile area northeast of the cut slope. The proposed fill area is outlined on Figure 4.7-4. In the placement of the fill, materials will be spread in layers approximately 12 inches deep, and such lifts made uniformly over long stretches and for the full width of embankment. Each lift will be moistened or dried to a uniform moisture content suitable for maximum compaction. Hauling equipment will be routed both ways over the fill and routing varied sufficiently to achieve uniform compaction. Compaction shall be carried to the edge of the fills so that the final slopes are firm. A sheepsfoot roller or other suitable equipment may be used in lieu of equipment routing to achieve compaction. Where the embankment is placed against the existing slope, the slope will be benched and scarified down to a firm dense base as the new fill is being placed. Material so loosened shall be mixed with the new fill and the resultant mix blended firmly . into the slope. NCIG - Coal Ridge No. i 4-56 08-04-95